1. Field of the Invention
The present invention relates to clip-on sunglasses and more particularly to an improved bridge member for clip-on sunglasses that enables the sunglasses to be mounted on eyeglasses in which the bridge of eyeglasses lies at least partially out of the plane of the eyeglass lenses, with the bridge member of the sunglasses in alignment with the protruding bridge of the eyeglasses.
2. Description of Prior Art Including Information Disclosed Under 37 CFR 1.97 and 1.98
Clip-on sunglasses consist of a metal or plastic frame that carries a pair of light attenuating plastic or glass lenses. A mechanism is provided to removably mount the clip-on sunglasses on the frame of eyeglasses.
In order to be commercially acceptable, the clip-on sunglasses must be light in weight, reasonably rugged and relatively inexpensive. They must also be easy to mount onto and remove from eyeglasses. Further, the clip-on sunglasses must mount without damaging the eyeglasses, particularly the lenses.
One common type of mounting mechanism is a clamp that is attached to the bridge of the sunglasses. The clamp typically has pairs of opposing prongs that are spring-loaded toward each other so as to retain the lenses of the eyeglasses therebetween. Examples of this clamping-type mechanism are disclosed in U.S. Pat. No. 3,575,497 issued Apr. 30, 1971 to Leblanc, U.S. Pat. No. 5,164,749 issued Nov. 17, 1982 to Shelton and U.S. Pat. No. Des. 350359 issued Sep. 6, 1994 to Friedman.
However, clamp-type mechanisms have their disadvantages. In order to secure the clip-on sunglasses, the prongs must clamp tightly to the lenses, potentially scratching the lenses. The mechanism may partially obstruct the view of the user. Moreover, clamp-type mechanisms have several inter-engaging parts which must be fabricated precisely and assembled, making the mechanism relatively expensive and sometimes unreliable.
In order to overcome the drawbacks of the clamp-type mechanisms, a different mechanism was developed for mounting clip-on sunglasses that does not contact or clamp the lenses of the eyeglasses and therefore cannot scratch them. Instead of a clamp, it utilizes one or more sets of exposed spring-loaded prongs. The prongs are movably or flexibly mounted such that they can be moved against a spring force, for insertion between spaced portions of the eyeglasses frame. The spring force causes the prongs to frictionally engage the eyeglasses frame. Because the prongs only engage the frame, the lenses of the eyeglasses cannot be scratched. An example of such a mechanism is disclosed in U.S. Pat. No. 5,953,096 entitled “Universal enter Bridge Mounting Mechanism for Clip-On Sunglasses” issued to Friedman on Sept. 14, 1999.
Another type of clip-on sunglasses, such as is disclosed in Lockwood U.S. Pat. No. 2,926,563, consists of mirror image frame sections, each of which includes of a lens and a bridge element. The bridge elements are connected together by a bridge mechanism that includes an exposed metal coil spring. Each frame section, at its outer extremity, is provided with a set (typically two or three) of spaced eyeglass frame engaging prongs protruding rearwardly from the plane of the lens sections. The spring bridge mechanism permits the frame sections to be moved away from each other, against the force of the spring. When the frame sections are moved away from each other, the eyeglasses frame can be inserted between the prong sets. Releasing the frame sections permits the spring to move frame sections back toward each other, such that the eyeglass frame is securely retained between the prongs sets.
One problem inherent in the Lockwood type spring bridge mechanism is that the coil spring is exposed. Aside from being unsightly, this is undesirable because bits of solid debris and other particulate foreign matter can lodge between the coils and jam the mechanism or distort the spring. Liquid, such as rain or sweat, can enter the mechanism resulting in rusting or deterioration of the parts. Further, the skin, hair and eyebrows of the user are not protected from being pinched by the exposed spring.
I therefore developed an improved spring bridge mechanism that overcomes the exposed spring problem by enclosing the coil spring within a slender metal tubular enclosure. The enclosure isolates the spring from the skin and hair of the wearer and prevents debris and liquids from reaching the spring.
The enclosure serves the additional purpose of keeping the frame sections in the proper plane as they are moved. This is achieved by forming an axially extending slot in the enclosure which cooperates with a protrusion to maintain the frame sections in the same plane.
The enclosure also enhances the appearance of the clip-on sunglasses by hiding the unslightly spring. Preferably, the enclosure is made of the same material and finish as the bridge elements and frame, resulting in a mechanism which is much more aesthetically pleasing than an exposed spring.
I received U.S. Pat. No. 6,234,528 issued May 22, 2001, U.S. Pat. No. 6,302,538 issued Oct. 16, 2001, U.S. Pat. No. 6,685,314 issued Feb. 3, 2004, U.S. Pat. No. 6,773,105 issued Aug. 10, 2004 and U.S. Pat. No. 6,869,179 issued Mar. 22, 2005 for various embodiments of my enclosed spring bridge mechanism invention.
With the exception of the enclosed spring bridge mechanisms disclosed in U.S. Pat. No. 6,685,314 and U.S. Pat. No. 6,869,179, enclosed spring mechanisms are generally not designed to align with the bridge of the eyeglasses upon which the clip-on sunglasses are mounted. Accordingly, it makes no difference if the bridge of the eyeglasses extends beyond the plane of the lenses of the eyeglasses because it will not interfere with the bridge mechanism of the clip-on sunglasses.
However, in a configurations such as shown in U.S. Pat. No. 6,685,314 or in U.S. Pat. No. 6,869,179, where the bridge mechanism of the clip-on sunglasses is designed to align with the bridge of the eyeglasses upon which the sunglasses are mounted, an eyeglass bridge that protrudes out of the plane of the eyeglass lenses will interfere with the bridge mechanism of the clip-on sunglasses and prevent the clip-on from being properly mounted on the eyeglasses. This is because the bridge mechanism of the clip-on sunglasses cannot bend or flex to accommodate the protruding bridge of the eyeglasses. Since many, if not most, eyeglasses have bridges that at least partially extend out of the plane of the lenses, and none of the known enclosed spring bridge mechanisms is bendable or flexible, none can be used in situations in which the enclosed spring bridge mechanism must align with the protruding bridge of the eyeglasses.
It is, therefore, a primary object of the present invention to provide clip-on sunglasses capable of being mounted on eyeglasses having a bridge that at least partially extends outside of the plane of the lenses, with the bridge member of the clip-on sunglasses in alignment with the bridge of the eyeglasses.
It is another object of the present invention to provide clip-on sunglasses with a flexible and expandable bridge member.
It is another object of the present invention to provide clip-on sunglasses having a flexible and expandable bridge member capable of engaging the bridge of the eyeglasses so as to maintain alignment therebetween.
In another embodiment, the connecting member is made of elastic material. It may have an arcuate or rectangular cross-sectional configuration. Alternatively, the member may be bifurcated to define a bridge receiving recess.
Means are provided for attaching the ends of the connecting member to the first and second lens sections, respectively. Each attaching means includes an element fixed to the lens section. The element defines a recess into which the end of the member is received. Means are provided for retaining the end of the member within the element recess.
The connecting member urges the lens sections toward the proximate position.
The lenses of the eyeglasses are situated substantially in a plane. At least a portion of the bridge of the eyeglasses is situated outside the plane of the eyeglass lenses.